Maria Somerville’s on the edge of something big. The dreamy, soft-focus pop of her debut album is unlike anything else you’ll hear this year, and she’s picking up attention across Europe. So it’s not exactly a surprise that the Bello Bar is wedged this evening: it’s wall-to-wall hipster, the barman’s sweating and under pressure as the orders come in faster than he can serve, and there are local journos, scenesters and musicians bouncing from one side of the venue to the other to meet and greet. The Bello Bar’s a small basement room, with a low-ceilinged area near the bar…